This specification is directed generally to ranking modifications of a previous query, such as modifications of a previous query that are based on a current query.
Internet search engines provide information about Internet accessible documents such as web pages, images, text documents, and/or multimedia content. A search engine may identify the documents in response to a user's search query that includes one or more search terms. The search engine ranks the documents based on the relevance of the documents to the query and the importance of the documents and provides search results that include aspects of and/or link to the identified documents. The user's search query may optionally be modified and such modified search query utilized in identifying one or more of the documents. For example, a misspelling in a search query may be corrected to create a modified search query and such modified search query utilized in identifying one or more of the documents. Also, for example, a term in a search query may be replaced with a synonym of that term to create a modified search query and such modified search query utilized in identifying one or more of the documents.